Torus converter for surface model

This MR adds the torus converter for the surface model.

Therefore, the torus surface needed to be added, including a solver for the intersection of a ray with the torus. The solver was adopted from the TorusImplementation2.h from the solid model.

Currently, there is no bounding tube for the torus, such that the expensive quartic equation must always be solved. Furthermore, the Newton iterations to refine the hits currently is done before doing a simple normal check, because otherwise the normal could be flipped, failing to give the correct hits. As soon as a bounding tube is added, this can be changed since we can locate to the bounding tube surface before solving the quartic equation for increased accuracy (same as is done in the solid model).